But in Windows 8.1 the ApplicationView is deprecated, developers can only know if the screen is in Landscape or Portrait. I implemented a helper class called ScreenManager to get the current screen mode, this class has also an Event to notify when the screen mode changed:

This class could be used to calculate the current screen mode and also to detect when it changes, we could for example shrink or hide some elements when the application is only taking a small portion of the screen. Of course it could be used to trigger a different VisualState.